my_dict = {'key1': 'value1', 'key2': 'value2'}

value_set = set(my_dict.values())
print(value_set)
target_value = 'value2'
if target_value in value_set:
    print(f"{target_value} 存在于字典中。")
else:
    print(f"{target_value} 不存在于字典中。")
